The remote host is missing an update to the system as announced in the referenced advisory FreeBSD-SA-06:25.kmem.asc
The firewire(4) driver provides support for IEEE 1394 (FireWire) interfaces. This driver provides some of its functionality via the ioctl(2) system call.
In the FW_GCROM ioctl, a signed integer comparison is used instead of an unsigned integer comparison when computing the length of a buffer to be copied from the kernel into the calling application.
Solution: Upgrade your system to the appropriate stable release or security branch dated after the correction date